Covert Investigations 2: Video Recording Devices

The care you use in selecting the right camera for a covert investigation can be undercut if you don't also choose the right video recording device

By Brandon Gregg

April 26, 2010 — CSO —

In the investigation at hand, we last left with our elusive suspect still painting the walls red at our manufacturing site's main office. While every reactive security measure has failed to identify and catch this finger-painting vandal, you have just selected your new low lux, infrared board camera after reading Covert Investigations: Cameras to catch your suspect red handed. (Literally.)

Also see the investigations primer Internal Investigations: The Basics

Unless you want to wire your new camera to a television and watch for hours live, your next, often underestimated step is selecting a video recording device to capture the incident for posterity. Much like the selecting your covert camera for size, resolution, lux level and power consumption, recording devices also have a few vital requirements to help you meet your goals. This time size is not an important issue; in my next column, covering covert installs, we will discuss setting up your recording device covertly near your camera or remotely across the globe. The real concerns in recording video are:

• Resolution (Again)
• Frames per decond (FPS)
• Retention requirements
• Recording device type

Even though you just spent a few hundred dollars on a state-of-the-art covert camera with 720 lines of resolution, if your recording device doesn't have equal or greater resolution, the video playback is going to suffer. Less lines of resolution means less detail to capture important identifiers that will help catch your suspect. Covert cameras and recording devices aren't magical tools that can record the inscribed name off your suspect's watch, closing the case between commercials. Instead, good resolution will help you clearly identify the suspect's face and other minor details that will hold up in a real court of law, not an episode of CSI. All reputable recording devices and their vendors will tell you the true resolution of the machine.

Frames per second (FPS or IPS) is a factor that many ignore until it's too late. In an attempt at saving storage space (retention), many recording devices remove frames from the image, making playback of the video look choppy. Instead of the fluid, natural movement of 30 frames per second, cheap recording/storage devices drop as low as 3 frames per second. Even the common 15 frames per second will show your suspect standing in one area and jumping across a room in the next frame.

The high price of saving money

Although great at reducing storage issues by over 50%, low frames-per-second make for an opening to miss something. The last thing a jury needs to see is a suspect holding stolen money one second and then not holding the money after a skipped frame. For a good example of how each frame per second looks compared to 30 frames per second, check out this simulation video: http://www.aventuracctv.com/howthingswork/fps.asp . Also make sure your recording device isn't being deceptive about its frames per second. Many devices that allow for multiple cameras lose frames per second as the numbers of cameras are installed. I prefer 30 frames per second per camera.

• Print

• Covert Investigations: Cameras
• How to Visualize Investigations
• The Rise of Anti-Forensics
• The Hidden Camera